Storage tank



Nov. 26, 1963 L. v. LARSEN ETAL 3,112,044

STORAGE TANK Filed April 12, 1961 2 Sheets-She et 1 IN V EN TORS Nov. 26, 1963 v V v. LARSEN ETAL 3,112,044

STORAGE TANK Filed April 12, 1961 2 Sheets-Sheet '2 srozaes TANk INVENTORS:

United States Patent Ofiice anneal Patented Nov. 25, 1963 3,112,044 sronAor. TANK Lyle V. Larsen, Summit, Nah, and Taavi Kanps, The

This invention relates to an improved underground storage tank and more particularly the means of corner and partition construction for tanks adapted to resist lateral active and passive earth pressures.

in many areas, products such as oil, gas and Water for fire reserves must be stored in buried tanks. The storage tanks are, depending upon the geology at the site, either buried wholly below the natural ground line or are positioned partially below natural ground and then covered with a substantial layer of earth. The most desirable shape, because of its inherent structural advantages for liquid storages, is the cylindrical flat bottom tank. However, in many areas real estate is so valuable that the entire area of a rectangular lot must be utilized. The instant invention economically provides novel angular corners for essentially rectangular tanks which cover virtually the entire area of such a lot. Prior to this invention the support system used in a square cornered tank was tremendously complicated, difiicult to erect and maintain, and did not provide the most efficient use of the constructing material.

When using scalloped walls it has heretofore been the practice to bring the corner scallop around in a 90 arc, using the same radius as used in the wall scallops. The present invention teaches that it is now not necessary to waste the land area associated with the use of such a circular corner.

The main problem in the construction of a square corner comes from the fact that the corner in question should be structurally balanced. When a buried tank is empty, the soil around it tends to put the tank under compressive forces whereas when such tank is full its liquid contents and vapor pressure tend to put the tank under tensional forces. Therefore, the use of relatively few members that can, and so positioned as to, withstand both the tensile and compressive forces is extremely advantageous. The instant invention teaches the use of sealloped panels running horizontally and attached and shaped to the scalloped walls, whereby the tensional or compressive force may be transmitted to the cross ties depending upon the direction of the applied loading. The scalloped panels at the corners are heavier than those used in the regular wall scallops because of their dual function of stitfening the wall and transmitting forces to the cross ties. Because of this simplified arrangement the exact size of the scalloped panels and cross ties may be simply computed. The number and spacing of the vertical rows of the horizontal cross ties depends upon the depth of the tank.

The invention also comprises one or more partitions which divide the tank into a plurality of chambers. The partition is similar in construction to the walls of the tank and it is joined to the walls, by means similar to the way in which the walls of the tanks are joined to each other, namely, by the use of cross ties which are welded, or otherwise joined, to the scalloped panels and stiifeners at their places of attachment or node points.

Other advantages will be seen when reference is made to the drawings and the remainder of the specification.

FTGURE l is a plan view of the storage tank showing the corner, partition, and wall supports thereof.

FIGURE 2 is a plan view of a corner of the storage tank.

FIGURE 3 isa cross-sectional view of the wall of the tank taken along line 3-3 of FIGURE 2'.

FEGURE 4 is a plan view of a corner of the storage tank showing a cross tie attached to two adjacent intersecting scalloped walls at their node points.

FIGURE 5 is a cross-sectional view of the storage tank showing an additional wall taken along line 5-5 of FIG- URE 6.

FIGURE 6 is a an additional wall.

FlIGURE 1 discloses a tank 1 with the novel corner and partition constructions of the present invention. Scalloped plates 2 in the instant application are composed of steel and are attached by welding them together along mutual vertical node lines to form the Walls 3 of the tank. Scalloped plates are employed because of their inherent structural advantages as compared with fiat plates. Scalloped panels 4 fit the contour of and are welded to the scalloped plates 2. The scalloped panels are strengthened by means of stifieners 5 which are welded thereto. Horizontally disposed cross ties 6 are welded to the place of attachment or mode points of each of the scalloped panels 4 at the corners of the tank. When the tank is empty these cross ties prevent the walls from buckling from the pressure of the earth or fill material which surrounds the buried tank. Conversely, when the tank is filled, wholly or in part, these cross ties prevent the walls from bulging. Securing the cross ties to the scalloped panels at their node points has been found to be structurally desirable and renders the corner structurally balanced.

Vertically extending columns 7 and 7' are welded to a roof 8 and a floor 9 of the tank. Columns 7 are also welded to each of the second vertical rows of horizontal cross ties at their midpoints, as shown in FIGURE 1. Columns 7 serve the dual function of supporting the roof 8 and the floor 9 of the tank and of rendering the cross ties more stable. Trusses ll) aid in reinforcing the walls 3 of the tank. These trusses are welded to the place of attachment or node lines of the scalloped plates 2 and are highly useful particularly in a tank having long walls.

It will be noted from FIGURE 2 that the scalloped panels 4 are constructed of a heavier section at the corners of the tank than are those along the remainder of the tank walls. This is because the corner scalloped panels serve the dual function of stilfening the walls of the tank and of transmitting forces to the cross ties.

As shown in FIGURE 4, a vertically extending column 11 is disposed between and welded to the ends of the scalloped panels and stitfeners; the ends of cross ties 6 are welded to the scalloped panels 4 and scalloped plates 2 at their places of attachment or node points. An angle iron 12 is disposed between and welded to the ends of the scalloped panels 4 and stiffeners 5.

A partition 13 divides the tank into two chambers, al-

plan view of the storage tank showing though it is to be understood that more than one parti-,

tion of the construction herein described can be employed. The partition or partitions, as the case may be, permit fluids different in kind to be kept separate and distinct from each other in the tank. The partition 13 also necessarily strengthens the tank and renders it more stable. As shown in FIGURE 1, the partition 13 comprises structural elements quite similar to those used in the construction of the walls 3 of the tank. Scalloped plates 2o, when attached at their ends for example by welding, form the partition wall 3a. Scalloped panels 4a fit the contour of and are welded to the scalloped plates 2a. The scalloped panels 4a are strengthened by means of stiffeners 5a which are welded thereto. Horizontally disposed cross ties 6a are welded to the places of attachment or node points of the scalloped panels 40. When the tank is empty the cross ties 6a prevent the partition l3 from buckling due to any give in the walls 3 caused by the earth or fill which surrounds the buried tank. Conversely, when, for example, one of the chambers formed by the partition wall is filled and other is empty the cross ties 6a prevent the partition from bulging. Vertically extending columns 7a are welded to the roof 8 and the floor 9 of the tank and to the second vertical row of horizontal cross ties 6a. Trusses 10a are welded to the scalloped panels 4 at their node points and aid in supporting the partition. Columns 11a are disposed between and welded to the ends of the scalloped panels 4a and stifieners a. Angle irons 12a are disposed at the end of the partition where the heavier section scalloped panels are located. One end of each of the cross ties 6a is attached by welding to the scalloped panels 4 in essentially the same manner as cross ties 6 are attached to the scalloped panels 4. A bracket 14 disposed on one side of the partition is welded to each of two adjoining scalloped plates 2a, to which the other end of each of the cross ties 6a are joined by welding. Of course, the other end of cross ties 6a might simply be welded to the place of attachment of two adjoining scalloped plates 2a. The cross ties on the other side of the partition are welded directly to the scalloped panels 4a and scalloped plates 2a at or near their node points. The scalloped panels 4 and 4a are made of a heavier section at the intersection of the partition 13 land the walls 3 for the reason pointed out above.

When it is required that one or more or all of the walls of the tank be further strengthened, the construction exemplified in FIGURES 1, 5 and 6 can be employed. One end of ties 15 are welded to the outer wall or walls of the tank at the places of attachment or node points of the scalloped plates 2. The other end of ties 15 can be welded to a second wall 16 having scalloped plates 18 and scalloped panels 17, or they can be simply imbedded in concrete as shown in FIGURE 1. The space between these two scalloped walls can be filled with earth or another suitable fill material. It is to be understood that the employment of the additional wall or walls 16 is optional.

The above-described embodiments being exemplary only, it will be understood that the present invention comprehends organizations differing in form or detail from the presently described embodiments. Accordingly, the invention is not to be considered as limited save as is consonant with the scope of the following claims.

We claim:

1. A corner construction for a storage tank comprising two adjoining walls extending in different horizontal directions and composed ofyertioally disposed scalloped plates joined at mutual vertical node lines, said corner construction comprising:

a pair of vertically disposed scalloped plates, one from each wall;

said pair of scalloped plates being joined together at a mutual vertical node line constituting a corner of said tank;

said pair of scalloped plates defining a vertically disposed, outwardly bulging corner portion, with said mutual vertical node line being the outermost extremity of the bulge;

said mutual vertical node line being in horizontal alignment with at least two other vertical node lines on each of said two walls;

scalloped strengthening means lying in a horizontal plane along the interior of each of said pair of scalloped plates;

and horizontally disposed reinforcing means extending from a non-mutual node line at said scalloped strengthening means on one of said pair of plates to a non-mutual node line at said scalloped strengthening means on the other of said pair of plates.

2. A corner construction as recited in claim 1 wherein:

each of said pair of scalloped plates has an arcuate horizontal cross-section constituting a sector of a circle circumscribed about a different center point than that for the other scalloped plate;

and each of said sectors is substantially less than 3. A corner construction as recited in claim 1 and comprising:

vertically disposed, stiffening means along the ins1de of each scalloped strengthening means.

4. A corner construction as recited in claim comprising:

a vertically disposed member at said corner between each of said scalloped strengthening means.

5. In a storage tank having a polygonal horizontal crosssection:

a plurality of walls each joining another at a tank corner portion, and each extending in a different horizontal direction than an adjoining wall;

each of said walls composed of a plurality of vertically disposed scalloped plates joined together at mutual node lines;

said tank corner portion including a pair of vertically disposed scalloped plates, one from each wall;

said pair of scalloped plates being joined together at a 1 and mutual vertical node line defining a corner of said bank;

said pair of scalloped plates defining a vertically disment with at least two other vertical node lines on each of said two walls.

6. in a storage tank as recited in claim 5:

scalloped strengthening means plane along the interior of each of said pair of sealloped plates;

and horizontally disposed reinforcing means extending from a non-mutual node line at said scalloped strengthening means one one of said pair of plates to a non-mutual node line at the scalloped strengthening means on the other of said pair of plates.

7. in a storage tank as recited in claim 5:

a plurality of adjoining outer walls each spaced outwardly from a respective one of said first recited walls and disposed substantially parallel thereto;

each of said walls composed of a plurality of vertically disposed scalloped plates joined together at mutual node lines;

earth fill between said first recited walls and said outer walls;

and horizontally disposed strengthening means extending from a node line on one of said first recited walls to a node line on the adjacent outer wall.

8. In a storage tank as recited in claim 7 wherein:

said strengthening means is substantially perpendicular to the two walls between which it extends.

References Cited in the file of this patent UNITED STATES PATENTS 1,864,931 Pritchard June 28, 1932 2,295,103 'Friedly Sept. 8, 1942 2,431,693 Horton Dec. 2, 1947 2,433,335 Boardman Dec. 30, 1947 2,673,001 Ulm Mar. 23, 1954 2,818,191 Arne Dec. 31, 1957 FOREIGN PATENTS 862,235 France a Nov. 30, 1940 lying in a horizontal- 

1. A CORNER CONSTRUCTION FOR A STORAGE TANK COMPRISING TWO ADJOINING WALLS EXTENDING IN DIFFERENT HORIZONTAL DIRECTIONS AND COMPOSED OF VERTICALLY DISPOSED SCALLOPED PLATES JOINED AT MUTAUAL VERTICAL NODE LINES, SAID CORNER CONSTRUCTION COMPRISING: A PAIR OF VERTICALLY DISPOSED SCALLOPED PLATES, ONE FROM EACH WALL; SAID PAIR OF SCALLOPED PLATES BEING JOINED TOGETHER AT A MUTUAL VERTICAL NODE LINE CONSTITUTING A CORNER OF SAID TANK; SAID PAIR OF SCALLOPED PLATES DEFINING A VERTICALLY DISPOSED, OUTWARDLY BULGING CORNER PORTION, WITH SAID MUTUAL VERTICAL NODE LINE BEING THE OUTERMOST EXTREMITY OF THE BULGE; SAID MUTUAL VERTICAL NODE LINE BEING IN HORIZONTAL ALIGNMENT WITH AT LEAST TWO OTHER VERTICAL NODE LINES ON EACH OF SAID TWO WALLS; SCALLOPED STRENGTHENING MEANS LYING IN A HORIZONTAL PLANE ALONG THE INTERIOR OF EACH OF SAID PAIR OF SCALLOPED PLATES; AND HORIZONTALLY DISPOSED REINFORCING MEANS EXTENDING FROM A NON-MUTUAL NODE LINE AT SAID SCALLOPED STRENGTHENING MEANS ON ONE OF SAID PAIR OF PLATES TO A NON-MUTUAL NODE LINE AT SAID SCALLOPED STRENGTHENING MEANS ON THE OTHER OF SAID PAIR OF PLATES. 